Ballast tamping assembly



Feb. 25, las@ F. PLASSER ETAL BALLAST TAMPING ASSEMBLY Filed Aug. 1,1967 Shee'rl of 2 E 1&.E l

PRIOR ART Aewr Feb. 25, i969 F. PLAssER ETAL.

BALLAST TAMPING ASSEMBLY Sheet Filed Aug. 1, 1967 INVENTORS, @MAIL msT032? THQ/Q AGM United States Patent i 3,429,277 BALLAST TAMPINGASSEMBLY Franz Plasser and Josef Theurer, both of .Iohannesgasse 3,Vienna, Austria Filed Aug. 1, 1967, ser. No. 657,616 Claims priority,application Austria, Aug. 5, 1966,

A 7,543/66 U.S. Cl. 104-12 Int. Cl. E01b 27/20 7 Claims ABSTRACT F THEDISCLOSURE Background and summary of the invention The present inventionrelates to improvements in track ballast tamping assemblies whereinpairs of opposing tamping tools are mounted on a common cam shaft forvibration.

In conventional assemblies of this type, the tamping tools of each suchpair are linked to a respective one of a pair of carrier arms extendingin opposite directions from the cam shaft, and are arranged forreciprocation towads and away from each other in the direction ofelongation of the track. Each arm has an inner end constituting a meansfor mounting the arm on the cam shaft for vibration of the arm uponrotation of the shaft, the mounting means of one arm being adjacent tothe mounting means of the other arm in the axial direction of the shaft.In this Way, the planes defined by the carrier arm mounting means areadjacent each other. Thus, the forces exerted on the shaft by thetamping tools upon reciprocation of the tools extend in spaced planesperpendicular to the cam shaft, thus imparting a bending moment to thecam shaft.

It is the primary object of this invention to overcome this disadvantageand thus to eliminate any torque applied to the cam shaft during thetamping stroke of the opposing tamping tools.

This and other objects are accomplished in accordance with the inventionby so constructing the mounting means of the carrier arms that theirplanes of symmetry extending perpendicularly to the cam shaft extend ina common plane.

In a specic embodiment, the inner end of one of the carrier arms isforked to define the plane of symmetry between the forks of the innerend, and the inner end of the other arm extends in the plane of symmetrybetween the forks.

The arrangement is particularly useful in recently developed tampingtool assemblies with two pairs of opposing tamping tools, which areadjacent each other in the direction of track elongation. In suchassemblies, each of the adjacent pairs of tools is arranged forreciprocation towards and away from each other. One of the tools of eachpair is linked to a respective one of the outer ends of the carrierarms, and the other one of the tools of each pair is linked to arespective one of the carrier arms intermediate its ends.

Brief description of drawing The above and other objects, advantages andfeatures of the present invention will be more fully understood byreference to the following detailed description of now pre- 3,4292??Patented Feb. 25, 1969 ferred embodiments, taken in conjunction with thedrawing wherein FIG. 1 is a schematic side view of one embodiment of aballast tamping assembly according to this invention;

FIG. 2 is a. transverse section, taken in the horizontal plane passingthrough the cam shaft along line II-II of FIG. 1, of a conventionalcarrier arm mounting;

FIG. 3 is similar to FIG. 2, showing an embodiment of the carrier armmounting according to the invention;

FIG. 4 is a side View of another embodiment of a ballast tampin-gassembly; and

FIG. 5 is a section along line V-V of FIG. 4 showing a carrier farmmounting similar to that of FIG. 3.

Detailed descriptiony The tamping tool assembly schematically shown inFIG. 1 is generally conventional, except for the features morespecifically described in connection with FIGS. 2 and 3, and may takethe specific form more fully described and illustrated in our U.S.Patent No. 3,000,327, dated Sept. 19, 1961, for example. For simplicityssake, the mounting of the tamping tool assembly on the tamping toolcarrier of a track tamper and t-he hydraulic reciprocating drive for theopposing tools has not been shown, such features being well known andfound, for instance, in our prior patent which also fully describes thetamping operation.

The assembly comprises a common cam shaft 1 extending transversely ofthe direction of elongation of the track and rotatable by a suitabledrive (not shown). A pair of carrier arms 2, 3 extend in oppositedirections from the cam shaft in the direction of the track elongation.Each carrier arm has an outer end to which a respective one of thetamping tools 5, S is linked by respective pivot 4, 4. Each tamping toolhas a pivot 8 intermediate its ends, at which point the reciprocatingmechanism (not shown) for the pair of opposing tools is linked to thetools. In this manner, operation of the reciprocating mechanism androtation of the cam shaft 1 will impart :a vibratory motion to thetamping tools and simultaneously move them together or apart, theapproachin'g movement causing any ballast between the tamping tools tobe compacted in a well known manner.

The inner end 2', 3 of each carrier arm constitutes a means mounting therespective :arm on cam shaft 1 for vibration of the arm upon rotation ofthe cam shaft in a manner more clearly shown in FIG. 2. The mountingends 2', 3 of the carrier arms are adjacent each other in the axialdirection of the shaft 1 .and the carrier arms are accordingly crankedto place the outer ends in the same vertical plane perpendicular to thecam shaft. As shown by arrows P and P", the forces transmitted to shaft1 by the carrier arm ends 2', 3 are yspaced apart on each side of theplane of symmetry lso that two forces are transmitted to the shaft,which impart a bending moment thereto.

According to the invention, as exemplified in the embodiment of FIG. 3,the planes of symmetry of the carrier arm mounting ends 2a' and 3a',which extend perpendicularly to the cam shaft 1, extend in a commonplane so that the force P exerted by the arms on the shaft operates in asingle plane. In the illustrated embodiment, the inner end 3a of theother carrier arm 3a is forked to define the plane of symmetry betweenthe forks of the inner end, and the inner end 2a' of the other :carrierarm 2a' extends in this plane of symmetry between the forks. Bendingmoments and torque exerted upon the shaft are thus reduced to a minimum.

FIG. 4 shows a tamping tool assembly as more fully described and claimedin our U.S. patent application Ser. No. 643,972, filed June 6, 1967.This assembly comprises vibratory shaft 1a supported on tamping toolcarrier 9. Carrier arms 2b, 3b extend from the vibratory shaft indiametrically opposite directions, the full mounting of the assembly ona mobile track tamper moving on the track not being illustrated becauseit is well known and has also been fully described and illustrated inour copending Patent No. 3,357,366, liled Feb. 17, 1966.

In this embodiment, the track tamping tool assembly comprises two pairsof tamping tools, each pair designed to tamp a tie positionedtherebetween. As is also conventional, the tamping tools comprisepivotal levers 5a, Sa and 5', 5', respectively, which are pivotallysecured intermediate their ends to fulcrums 8', 8' and 12, 12,respectively. Fixed fulcrums 12, 12 are pivotally secured to each lever5', 5 of the adjacent tamping tools of the adjacent pairs of the tools,and the means for elfectuating the reciprocation of the adjacent toolsconsists of hydraulic motors 13 whose piston rods are respectivelylinked to each of the upper ends 14 of the adjacent tamping tools formoving the upper tool ends in the direction of elongation of the track.

As shown, the cylinders of the hydraulic motors 13 are linked to theouter ends of the carrier arms 2b, 3b at pivots 15, 15 so that thevibration of the arms is transmitted to the tamping tools via theirreciprocating devices.

Fulcrums 8 of the tamping tool levers 5a, which support the tamping tooljaw mounts 6 with their tamping jaws 7, are mounted for movement in thedirection of track elongation and are secured to slidable supports 8amounted on support rails 11 carried by brackets 10 in tamping toolcarrier 9, all in a manner well known per se. As also fully described inour copending Patent No. 3,357,366, the tamping tool reciprocatingdevice includes piston rod 8" attached to the slidable supports andgliding in a stationary cylinder positioned centrally of the adjacentpairs of tools.

The tamping tool jaw mounts 6', 6 of the adjacent tamping tools arecranked in the manner more fully described and claimed in our copendingapplication Ser. No. 643,972.

The arrangement of the inner carrier arm mounting ends 2b and 3b' is thesame as described in connection with FIG. 3, as shown in FIG. 5.

While a specific embodiment of the carrier arm mounting on the cam shafthas been described and illustrated, it will be understood that manymodifications and variations may occur to those skilled in the art,particularly after beneiitting from the present teaching, withoutdeparting from the spirit and scope of the present invention as definedin the appended claims.

We claim:

1. An assembly for tamping ballast comprising (l) a cam shaft;

(2) a pair of carrier arms extending in opposite directions from the camshaft,

(a) each of said arms having an outer end and an inner end constitutinga means mounting the arm on the cam shaft for vibration of the arm uponrotation of the cam shaft, and

(b) each arm mounting means having a plane of symmetry extendingperpendicularly to the cam shaft, the planes of symmetry of said armmounting means extending in a common plane; and

(3) a tamping tool linked to each one of the outer ends of the carrierarms,

(c) the pair of tamping tools being arranged for reciprocation towardsand away from each other. 2. The ballast tamping assembly of claim 1,wherein said common plane defines a plane of symmetry of the 5 carrierarms.

3. An assembly for tamping ballast comprising (l) a cam shaft;

(2) a pair of carrier arms extending in opposite directions from the camshaft,

(a) each of said arms having an outer end and an inner end constitutinga means mounting the arm on the cam shaft for vibration of the arm uponrotation of the cam shaft, and

(b) each arm mounting means having a plane of symmetry extendingperpendicularly to the cam shaft, the planes of symmetry of said armmounting means extending in a common plane; and

(3) two pairs of opposing tamping tools,

(c) each of said pairs of tamping tools being arranged for reciprocationtowards and away from each other, and

(d) one of the tamping tools of each pair being linked to a respectiveone of the outer ends of the carrier arms, and the other one of thetamping tools of each pair being linked to a respective one of thecarrier arms intermediate its ends.

4. The ballast tamping assembly of claim 3, wherein the inner end of oneof said carrier arms is forked t0 define said plane of symmetry betweenthe forks of the inner end, and the inner end of the other carrier armextends in said plane of symmetry between the forks.

S. The ballast tamping assembly of claim 3, wherein said common planedefines a plane of symmetry of the carrier arms.

6. An assembly for tamping ballast comprising (l) a cam shaft;

(2) a pair of carrier arms extending in opposite directions from the camshaft,

(a) each or" said arms having an outer end and an inner end constitutinga means mounting the arm on the cam shaft for vibration of the arm uponrotation of the cam shaft,

(b) the inner end of one of said carrier arms being forked to define aplane of symmetry extending perpendicularly to the cam shaft between theforks of the inner end, and

(c) the inner end of the other carrier arm extending in said plane ofsymmetry between the forks; and

(3) a tamping tool linked to each one of the outer ends of the carrierarms,

(c) the pair of tamping tools being arranged for reciprocation towardsand away from each other.

55 7. The ballast tamping assembly of claim 6, wherein said common planedefines a plane of symmetry of the carrier arms.

References Cited UNITED STATES PATENTS 9/1961 Plasser et al 1011-121/1962 Plasser et al 104-12

